ID number 4 of data not working

[Vishesh-Verma-Work]

it is because it is written like this :
{
_id: 4,
title: "Started React JS",
content:
"Made my first App in React JS, feels awesome to learn something new. I aim to be a full stack dev someday",
category: "Learning",
},

and should be written like this :

{
_id: "4",
title: "Started React JS",
content:
"Made my first App in React JS, feels awesome to learn something new. I aim to be a full stack dev someday",
category: "Learning",
},

just the difference of, 1st line :

_id: 4, to _id: "4",

[Vishesh-Verma-Work]

fix this